Military drones rely heavily on GPS for navigation guidance while in the air. But in areas where a signal can't be found, or where someone is using a GPS jammer, a drone will find itself in a troublesome predicament. Military sub-contractor BAE Systems has come up with a solution to that problem: A positioning system called NAVSOP that uses any wireless signal to find its location.

The genius of NAVSOP (Navigation via Signals of Opportunity) is that it really doesn't matter what the signal is. It can be a TV signal, radio signal, wi-fi signal, or even a GPS jamming signal. And the part that excites BAE is that the infrastructure is already in place. They don't have to build out a network of transmitters. What excites us is that it works indoors, meaning if this was integrated into all navigation products—and not just military tools—we could have powerful location assistance services indoors and in dense cities. The BBC says that the NAVSOP box requires GPS at first to learn about its surroundings. But over time as it amasses a database of location information, it will become less and less reliant on GPS.

The system is currently a prototype box that can be linked up to whatever is in need of navigation assistance, but BAE believes it can be shrunk down into a dongle-sized package.It's like the navigation equivalent of the tech Bruce Wayne used in Batman Begins to see through walls using people's cellphone signals. [BAE via BBC via Engadget]